Produce your citation, don’t just name-drop. Augustine said many things.
Augustine (354-430):
“In a passage in this book, I said about the Apostle Peter: ‘On him as on a rock the Church was built.’ . . . But I know that very frequently at a later time, I so explained what the Lord said: ‘Thou art Peter, and upon this rock I will build my Church,’ that it be understood as built upon Him whom Peter confessed saying: ‘Thou art the Christ, the Son of the living God,’ and so Peter, called after this rock, represented the person of the Church which is built upon this rock, and has received ‘the keys of the kingdom of heaven.’ For, ‘Thou art Peter’ and not ‘Thou art the rock’ was said to him. But ‘the rock was Christ,’ in confessing whom, as also the whole Church confesses, Simon was called Peter. But let the reader decide which of these two opinions is the more probable.” (The Retractions, 1:20:1)
https://carm.org/early-church-fathers-peter-the-rock
I have not read all of Augustine, so correct me if I am wrong. But didn’t Augustine believe that Jesus appointed Peter to be the leader of the Catholic Church?